Electrical fuse head and method of manufacturing same



C. C. JESSEN.

ELECTRICAL FUSE HEAD AND METHOD OF MANUFACTURING SAME.

APPLICATION FILED IUNE23, I921.

Patented Feb. 21, 1922.

LADTi LW/D me/wtoz UNHTEEDD STATES CHARLES C. J'JESSEN, OF T 5.

QUA, PENNSYLVANIA, ASSIGIX TOR TO ATLAS POWDER A COMEANY, OF WILMINGTON, DELAWARE A CORPORATION OF DELAWARE.

ELECTRICAL FUSE HEAD AND METHOD OF MANUFACTURING SAME.

To all whom it may concern:

Be it known that I, CHARLES C. JEssEN, a citizen of the United States of America, residing at Tamaqua, in the county of Schuylkill and State of Pennsylvania, have invented certain new and useful Improvements in Electrical Fuse Heads and Methods of Manufacturing Same, of which the following is a specification.

This invention relates to an electrical fuse head and method of manufacturing the same, said fuse head being of the nature of those shown in the Schmitt and Krannichfeldt Patents 720073 February 10, 1903 and 722913 of March 17, 1903. 1

It is one of the objects of the present invention to provide a novel correlation and assembly of the parts by virtue of which the structure will lend itself to rapid and accurate manufacture by automatic machinery with a consequent marked economy in the production of the finished article.

In the manufacture of'fuses of this nature in accordance with the Schmitt and Krannichfeldt patents, it has been customwhat flimsy nature of the nonconducting material, a great deal of material is destroyed in the manufacture of the finished article.

According to the present invention the main backing or supporting element, upon which the successive operations are performed during manufacture consists of a metallic and conducting part which is not only strong and stiff enough to stand up under the several steps to which it is subjected, but, additionally, is adapted to have a second metallic and conducting part clipped thereto with a piece of insulating material bound therebetween, so that the entire assembly may be effected without the necessity of pasting or sticking any of the parts together.

Further objects and advantages of the Specification of Letters Patent;

Application filed June 23, 1921.

Patented Feb. 211, 11922.

semn no. 479,766.

invention will be set forth in the detailed description which follows. 7

In the accompanying drawing:

Fig. 1 is an elevation of a foundation strip of metallic conducting material upon which the succeeding operations in the manufacture of the complete articles are performed;

Fig. 2 is a view similar to Fig. 1 looking from the opposite side thereof and illustrating the other metallicand conducting terminals clipped thereto;

Fig. 3 is a sectional view through the structure illustrated in Fig. 2 and upon line 33 of Fig. 2;

Fig. 4 is an elevation of one of the me-- tallic crimp terminals;

Fig. 5 is an elevation of one of the insulating pieces which are cli ped between the crimp terminals and the foundation strip;

Fig. 6 is a magnified sectional view through the completed fuse head;

Figs. 7 and 8 are detail views illustrating a sh htly modified form of the invention.

Li e numerals designate corresponding parts throughout the several figures of the drawing.

In carrying out the manufacture of a fuse head in accordance with the present invention, a strip of thin sheet metal, which may be in ribbon form to facilitate its use in automatic machinery, is coated upon one side with an insulating paint or varnish, such as Arma-lac, Jap-a-lac, ordinary varnish or the like. When this coating of insulating material is dry the sheet metal ribbon is punched to produce a comb-like structure 5,

one side of which is free of insulating mate rial and the other side of which is coated with insulating material 6. The back 7 of the comb-like structure constitutes a su port for the legs 8, which legs. ultimate y constitute one of the metallic or terminal sides of the completed fuse head. Crimp terminals 9 are stamped from sheet metal of substantially the thickness of that used in the production of the structure of Fig. 1, and these crimp terminals are provided with laterally-extending cars 10 adapted to be crimped or bent firmly about the legs .8 to

bind the two metallic terminals together.

Insulating pieces 11 of any suitable material, but preferably of paper, are stamped out in a shape corresponding with the shape of the crimp terminals 9, and these insulating pieces are provided with laterally extending ears 12 which'are engaged beneath the corresponding ears 10 of the crimp terminals, so that insulating material not only lies between the body of the crimp terminals and the adjacent faces of the legs 8 but also lies between the ears 10 and the legs 8 throughout the confronting surfaces of these parts.

It is to be noted that the crimp terminals are somewhat shorter than the legs 8, with the result that portions 13 of the legs 8 are left projecting beyond the lower ends of the crimp terminals. This renders it'possible to extend a fine wire 14, adapted to become incandescent when an electric current is passed therethrough, from the extremity of the crimped terminal to the extremity of the legs 8, while leaving said wire in spaced relation to the face of legs 8 throughout the major portion of the length of said wire. Electrical contact is made between said wire and the respective terminals by means of drops of solder, indicated at 15. However it is to be additionally noted that the wire lies adjacent a face of the legs 8 which has been rendered nonconductive by the coating 6.

After the wires 14 have been applied the lower ends of the legs are dipped into a body of inflammable or explosive material and forms globules 16. The method of manufacture and the construction herein shown and described insures great accuracy and uniformity in the manufacture of the finished product, because the terminals are positively held from shifting position with respect to each other, are efficiently insulated from each other and since the dipping of the legs into the plastic mass may be effected before the legs 8 are severed from the backing 7, absolute uniformity in dipping may be achieved, as, for exam 1e, by the means illustrated in Fig. 7 of the chmitt and Krannichfeldt Patent 720073.

After the globules have been formed upon the lower ends of the legs, said legs are severed from the backing 7 ust above the tops of the crimp terminals and conducting wires 17 and 18 are soldered to the respective terminals of the finished fuse heads.

In Figs. 7 and 8 I have illustrated a slightly modified form of the device wherein the ears 10' instead of being formed upon the crimp terminals are formed upon the legs and are bent about the terminals 9.

Otherwise the structure is the same as hereinbefore described.

- It is to be understood that the inventionis' a part of the insulating material about the 7 other of said metallic terminal elements.

2'. The herein described method of manufacturing electrical fuse heads which consists of forming a conducting metallic backing member comprising a'plurality of legs and a part uniting said legs, crimping into engagement with said legs additional metallic conducting elements and interposed pieces of insulating material and thereafter separating said legs from the remainder of the structure.

3. A fuse head of the character described comprising a pair of metallic conducting terminals, one of which has a pair of laterally extending ears formed thereon, a piece of insulatingmaterial having corresponding laterally extending ears, the ears of the conducting material and the ears of the insulating material being crimped about the other piece of conducting material and a globule of ignitible material embracing the. ends of said terminals.

4:. A fuse head of the character described comprising a pair of sheet metal terminals one of which is provided with a pair of ears adapted to be crimped about the other, a sheet of interposed insulating material having corresponding ears, one of said metallic terminal elements being shorter than the other, a wire adapted to become incandescent when an electric current is passed therethrough extending between the ends of said metallic terminals and a globule of ignitible material embracing said wire and the terminal ends of the metallic terminals,

5. A structure as recited in claim 4; wherein that face of one of said metallic terminals which lies toward the other of said terminals is covered with an insulating coating.

In testimony whereof I aflix my signature in the presence of two witnesses.

CHARLES C. J ESSEN.

Witnesses:

W. G. FRYE, W. F. MARCH. 

